I've successfully removed bird poop marks by using a clear coat cleaner and a swirl remover. As long as the poop didn't etch too far into the clear coat, it will get a lot of the damage out, and if your lucky, all of it. On the other hand, I have a spot on the roof of my car where bird poop ate down to the primer coat. Wax by itself isn't likely going to get all the damage out.